Project Summary/Abstract About 300,000 U.S. workers per year incur serious work injuries resulting in permanent impairment and a permanent partial disability (PPD) award. There are significant knowledge gaps regarding the extent of return- to-work (RTW) interruption and re-injury among permanently impaired workers as well as the contextual factors that may be amenable to workers' compensation (WC) system-level interventions. The objectives of this study are to quantify RTW interruption and re-injury for workers who have RTW after a work-related permanent impairment, and to identify and prioritize the salient contextual factors. The central hypothesis is that workers with PPD are at elevated risk of RTW interruption and re-injury, particularly in the first year after RTW, which may be mitigated via potentially modifiable contextual factors. This study will use linked WC and state wage data to measure long-term RTW patterns and re-injury. A representative survey of permanently impaired workers will be conducted to measure self-reported re-injury, health status, contextual factors, and worker- suggested solutions. Aim 1: Characterize the first year of labor market participation after claim closure with a PPD award. Aim 2: Quantify time-varying risks of RTW interruption and re-injury for permanently impaired workers who have RTW, compare to risks for injured workers without PPD, and assess the impact of worker/ injury/job characteristics on these outcomes. Aim 3: Prioritize modifiable workplace and WC-based contextual factors (e.g., safety climate, job strain, supervisor/coworker support) for future intervention development by testing associations with RTW interruption and re-injury among workers with PPD. This study will produce several expected outputs and outcomes. Aims 1 and 2 will provide evidence for the nature and magnitude of RTW interruption and re-injury that can be used to support policy changes or investment in interventions. Aim 3 will identify and prioritize modifiable workplace and WC-based contextual factors associated with RTW interruption and re-injury that may be amenable to WC system-level intervention. This research is significant because it will underpin future development of efficient large-scale cross-sector WC system-level interventions designed to sustain successful RTW in this priority population. This study is innovative because: (1) the focus is on modifiable contextual factors for RTW interruption and re-injury, rather than on worker attributes; (2) the worker survey is designed to identify previously unrecognized risk factors and worker-suggested solutions; (3) WC claims, wage data, and the survey will be used to measure re-injury and RTW after claim closure; and (4) disabled workers are an insufficiently-researched NIOSH priority population. This study will contribute to R2P by laying the groundwork, in collaboration with the state WC agency and stakeholders, for proactive focus of workplace and WC resources where most needed to facilitate sustained injury-free RTW for workers with PPD.